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ABSTRACTCombs have a significant role as substrates for Termitomycesin providing nutrients for Macrotermitinae colonies. However, the process of comb establishment was poorly known. The study was to observe the process of fungal comb formation of fungus-growing termites in the laboratory. Each pair of alates from three species, i.e Microtermes insperatusKemner, Macrotermes gilvusHagen, and Odontotermes bogoriensisKemner were reared and introduced to Termitomycessp. basidiospores, meanwhile another pairs that were not introduced to the basidiospores were acted as the control. M. insperatusintroduced with and without basidiospore established 100 % of developed combs and 33.33 % of developed combs respectively. M. insperatusthat succeed in making developed comb had a relatively similar pattern in growth of colony members between those introduced and not introduced with basidiospores, however, they were in contrast to M. insperatusthat did not succeed in making developed combs. M. gilvusand O. bogoriensisthat were or were not introduced with basidiospore established 0 % of the developed comb. The combs were observed for the first time in the 15thweek of the rearing period. The fungus in developed combs of M. insperatusintroduced to basidiospores and the culture of Termitomycessp. were in one clade with Termitomyces cylindricus.

The innovation in the proposed termite detection system can detect and predict the population non-destructively based on acoustic and temperature signals. This study aims to identify the characteristics of acoustic and temperature signals of subterranean termite infestation. Various termite populations were inserted into the pine board for 21 days as a feeding test, then infestation was monitored through the continuous acoustic-temperature signals response after 24 h. Based on the signal analysis, the peak of daily termite activity can be found in the afternoon, while the evening until early morning contained significantly less activity. This fluctuation was significantly associated with ambient temperature, the higher the temperature, the greater the activity. Furthermore, the signal analysis revealed that the higher the termite population, the warmer the board temperature with an average of 0.101°C. Based on the results, extensive knowledge is essential to effectively develop the signal processing package in the termite detection system.

Wettability and bonding quality of exterior coatings on fast-growing wood surfaces were studied. Samples of air-dried flat-grained (tangential surface) and edge-grained (radial surface) pattern of jabon (Anthocephalus cadamba) and sengon (Paraserianthes falcataria) woods were used. Before application of exterior coatings, the surfaces of the lumber samples were sanded. To provide wood surfaces with various degrees of roughness, abrasive papers of 120, 240, and 360 grits were used for the surface preparation. The wettability of two exterior coatings (water-based acrylic and oil-based alkyd varnishes) on the sanded wood surfaces was measured using a sessile drop contact angle method. The Shi and Gardner (S/G) model was used to evaluate and compare the wettability of the surface coatings on the wood. The sanded wood samples were coated with the two coatings (two layers each). Bonding quality of the coating layers was measured using a crosscut tape test method. Experimental results show that constant contact angle change rate (Kvalue) of the S/G model decreased as the grit number of abrasive paper increased. This indicates that the wettability decreased as the roughness of the surface decreased (surface becomes smoother). There was no evidence of differences in wettability between tangential and radial wood surfaces. The oil-based alkyd coating generated better wettability compared to the water-based acrylic. The crosscut tests showed that the bonding quality of the coating films on both jabon and sengon wood decreased as the surface became smoother. The sengon wood compared to jabon wood provided better coating wettability and bonding quality. Wettability in terms of the Kvalues was a good indication for determining the bonding quality of the two varnish layers.